Abstract Background Psychiatric morbidity is substantially higher in Northern Ireland (NI) than in peer nations and men are disproportionately represented in suicide mortality data, particularly at early adulthood and middle age. To better scale interventions to reduce morbidity and mortality among young men, a mixed-methods study was conducted combining interviews and validated quantitative tools. Methods A non-random community sample of 30 working-class young men in Belfast aged 16-19 was recruited via organisations focused on job training, restorative justice, and youth work. Participants completed the Self-Harm Inventory and a semi-structured interview. Analyses were completed in NVivo and RStudio. Results The prevalence of self-harm was more than 8 times higher than for the general population of adolescents in NI, with 83.3% reporting ever engaging in self-harm. Only 2 of the 28 participants reported making a suicide attempt and most injuries were minor, suggesting nonsuicidal self-injury (NSSI) represented almost all injuries. Although the sample had a higher risk profile than the general population-with high levels of trauma, substance use, and socioeconomic deprivation-participants also endorsed strong social connections to friends, family, and community. While many expressed concerns about sharing their own emotional distress, almost all reported that disclosures are important to avert poor mental health and shared times when they or friends sought support. Conclusions Although there was a high prevalence of NSSI in the sample, the low prevalence of suicide attempts may be associated with the high levels of protective social connections reported by participants. Gender-based concerns regarding emotional support were common, but there was also strong endorsement for the importance of seeking support from trusted relationships. This suggests that there may be an appetite for male role models to provide education around the “bravery” of help-seeking. Key messages • Prevalence of nonsuicidal self-injury may be substantially more elevated in some populations of adolescent males. • Gender-based concerns continue to act as a barrier to young men sharing their emotional distress with trusted individuals.